A5025063260- earthquake and tectonic studies
- High-pressure geophysics and materials
- Seismic Waves and Analysis
- Seismic Imaging and Inversion Techniques
- Seismology and Earthquake Studies
- Geological and Geochemical Analysis
- Geological and Geophysical Studies
- Methane Hydrates and Related Phenomena
- Underwater Acoustics Research
- Earthquake Detection and Analysis
- Geological Studies and Exploration
- Oceanographic and Atmospheric Processes
- Geophysics and Sensor Technology
- Underwater Vehicles and Communication Systems
- Geophysics and Gravity Measurements
- Geology and Paleoclimatology Research
- Hydrocarbon exploration and reservoir analysis
- Ocean Waves and Remote Sensing
- Geological Modeling and Analysis
- Reservoir Engineering and Simulation Methods
- Marine animal studies overview
- Geophysical Methods and Applications
- Geomagnetism and Paleomagnetism Studies
- Geophysical and Geoelectrical Methods
- Astro and Planetary Science
Kobe University
2016-2025
Japan Agency for Marine-Earth Science and Technology
2008-2020
The Ocean Foundation
2019
St. Luke's International University
2016
Earth University
2015
EarthSky
2015
Saiseikai Ibaraki Hospital
2009
The University of Tokyo
1996-2005
Abstract We present a new whole mantle P wave tomographic model GAP_P4. used two data groups; short‐period of more than 10 million picked‐up onset times and long‐period 20 thousand differential travel measured by waveform cross correlation. Finite frequency kernels were calculated at the corresponding bands for both long‐ data. With respect to an earlier GAP_P2, we find important improvements especially in transition zone uppermost lower beneath South China Sea southern Philippine owing...
Research Article| June 13, 2018 Development of a Slow Earthquake Database Masayuki Kano; Kano aEarthquake Institute, The University Tokyo, 1‐1‐1 Yayoi, Bunkyo‐ku, Tokyo 113‐0032, Japan, babasatoru@eri.u-tokyo.ac.jp, kano@eri.u-tokyo.ac.jp, obara@eri.u-tokyo.ac.jp, maeda@eri.u-tokyo.ac.jp, akiko-t@eri.u-tokyo.ac.jpqNow at Department Geophysics, Graduate School Science, Tohoku University, 6‐3 Aramaki Aza‐Aoba, Aoba‐ku, Sendai, Miyagi 980‐8578, Japan; masayuki.kano.a3@tohoku.ac.jp. Search for...
Extensive submarine pyroclastic deposits were discovered around the Kikai caldera, Southwest Japan, which originated from caldera-forming Kikai-Akahoya (K-Ah) eruption that occurred at 7.3 ka. This unit a density current (PDC) entered sea and was transformed into subaqueous current. Our high-resolution marine seismic reflection surveys reveal uppermost exhibiting prominent facies thins radially away caldera covers >4500 km2 of seafloor. The estimated volume is >71 km3 based on isopach map....
The anelastic structure of a subduction zone can place first‐order constraints on variations in temperature and volatile content. We investigate seismic attenuation across the western Pacific Mariana system using data from 2003–2004 Subduction Factory Imaging Experiment. This 11‐month experiment consisted 20 broadband stations deployed arc islands 58 semibroadband ocean bottom seismographs fore arc, island back‐arc spreading center. compute amplitude spectra for P S arrivals local...
A permanent real-time geophysical observatory using a submarine cable was developed and deployed to monitor seismicity, tsunamis, other phenomena in the southern Kurile subduction zone. The comprises six bottom sensor units, two branching main electro-optical with length of 240 km land stations. units are: 1) three ocean broadband seismometers hydrophone; 2) pressure gauges (PGs); 3) end station environmental measurement sensors. Real-time data from all undersea sensors are transmitted...
Shear wave splitting measurements provide significant information about subduction zone mantle flow, which is closely tied to plate motions, lithospheric deformation, arc volcanism, and backarc spreading processes. We analyse the shear of local S waves recorded by a large 2003–2004 deployment consisting 58 ocean-bottom seismographs (OBSs) 20 land stations nine OBSs from smaller 2001–2002 deployment. employ several methods data processing schemes, including spatial averaging methods, obtain...
The South Pacific region is characterized by a broadly elevated seafloor known as the superswell. This has concentration of midplate volcanoes that experienced massive eruptions in mid‐Cretaceous period (90–120 Ma). These characteristics suggest presence large‐scale mantle plume beneath Pacific, called superplume. geometry, origin depth, temperature, and composition superplume remain controversial, however, mainly due to lack seismological data documents structure Pacific. Seismic stations...
Abstract We have analyzed broadband surface wave data from ocean bottom seismometers deployed in the Shikoku Basin northeastern Philippine Sea to determine radially anisotropic uppermost mantle structure beneath this oceanic basin. first applied noise correlation method continuous microseismic records obtain phase velocities for fundamental‐mode and higher‐mode Rayleigh waves Love at periods of 7–29 s. At longer periods, we an array analysis teleseismic 29–117 Using these velocity...
Clear atmospheric pressure changes associated with the 2003 Tokachi‐Oki, Japan, earthquake Mw 8.3 were recorded microbarographs distributed in Japan. The change starts at arrival of seismic waves and reaches its maximum amplitude Rayleigh waves, suggesting that observed was driven by ground motion passing site. We computed seismic‐to‐pressure transfer function (i.e., spectral ratio to vertical velocity) for periods between 10 50 s from co‐located barograph seismograph records. Comparison...
We analyze seismic waveforms from deep‐focus earthquakes occurring in the subducting slab beneath Japan, recorded by broadband ocean bottom seismometers (BBOBSs) installed on northwestern Pacific Ocean seafloor. The data reveal with a low‐frequency direct P onset, followed large‐amplitude, high‐frequency, long‐duration Po and So waves. From analysis of BBOBS records numerical finite‐difference method simulation wave propagation, we elucidate generation propagation processes such guided...
Abstract The Ontong Java Plateau in the western Pacific Ocean is world’s largest oceanic plateau. It was formed 122 million years ago by a massive volcanic event that significantly affected Earth’s environment. cause of magmatic remains controversial because upper mantle structure beneath plateau poorly known. Here we use passive seismic data obtained through seafloor observations, alongside existing data, to determine three-dimensional radially anisotropic shear wave velocity depths up 300...
We conducted geophysical observations on the French Polynesian seafloor in Pacific Ocean from 2009 to 2010 determine mantle structure beneath Society hotspot, which is a region of underlying volcanic activity responsible for forming Islands. The network Tomographic Investigation by ARray Experiment hotspot (TIARES, named after most common flower Tahiti) composed multi-sensor stations that include broadband ocean-bottom seismometers, electro-magnetometers, and differential pressure gauges....
Anomalously large tsunamis generated by a submarine volcanic earthquake were recorded an ocean bottom pressure gauge array.
Abstract We conducted broadband dispersion survey by deploying two arrays of ocean bottom seismometers in the northwestern Pacific Ocean at seafloor ages 130 and 140 Ma. By combining ambient noise teleseismic surface wave analyses, curves Rayleigh waves were obtained a period range 5–100 s then used to invert for one‐dimensional isotropic azimuthally anisotropic β V ( SV ) profiles beneath each array. The show ~2% difference low‐velocity zone (LVZ) depth 80–150 km spite small horizontal...
Seismic imaging provides an opportunity to constrain mantle wedge processes associated with subduction, volatile transport, arc volcanism, and back-arc spreading. We investigate the seismic velocity structure of upper across Central Mariana subduction system using data from 2003–2004 Subduction Factory Imaging Experiment, 11 month deployment consisting 20 broadband stations installed on islands 58 semibroadband ocean bottom seismographs. determine three-dimensional VP VP/VS over 25,000 local...
Abstract We analyzed seismic ambient noise and teleseismic waveforms of nine broadband ocean bottom seismometers deployed at a 60 Ma seafloor in the southeastward Tahiti island, South Pacific, by Tomographic Investigation ARray Experiment for Society hotspot project. first obtained one‐dimensional shear wave velocity model beneath array from average phase velocities Rayleigh waves period range 5–200 s. The shows large reduction depths between 40 80 km, where lithosphere‐asthenosphere...
Secondary magnetic fields are induced by the flow of electrically conducting seawater through Earth's primary field ('ocean dynamo effect'), and hence it has long been speculated that tsunami flows should produce measurable perturbations, although signal-to-noise ratio would be small because influence solar fields. Here, we report on detection deep-seafloor electromagnetic perturbations 10-micron-order a tsunami, which propagated seafloor electromagnetometer array network. The observed data...